Students could read articles about how math is used and respond. Look at this example:
Metric Confusion


For math lessons, you could include examples of how math is used in the real world, and have students make their own wikipages to "sell" their product. For example, they could calculate the amount of wood needed to build a shelter, calculate the cost, and advertise their shelter. Advertisements could be placed on their page, and other students could respond to their ads using the discussion tab.